Oldest predator fish hailed from China

摘要

Enter the hunter. An extinct fish caWedMegamastax, which prowled the oceans 423 million years ago, is the earliest fish known to be a top predator. The find supports the idea that animals like us, with jaws and backbones, evolved in southern China. It could also help pin down when oxygen in the atmosphere first reached modern levels. Brian Choo, now at Flinders University in Adelaide, Australia, and colleagues studied a lower jaw and part of an upper jaw from south-west China. They say Megamastax was 1 metre long, with a 16-centimetre-long jaw. It had sharp teeth along the front to grip slippery prey and blunt teeth in the back to crush their shells (Scientific Reports, doi.org/s64).